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Levonorgestrel IUS

Oregon Health and Science University · FDA-approved active Small molecule

Levonorgestrel IUS is an intrauterine system that releases the synthetic progestin levonorgestrel directly into the uterus to prevent pregnancy through multiple mechanisms including cervical mucus thickening, endometrial suppression, and ovulation inhibition.

Levonorgestrel IUS is an intrauterine system that releases the synthetic progestin levonorgestrel directly into the uterus to prevent pregnancy through multiple mechanisms including cervical mucus thickening, endometrial suppression, and ovulation inhibition. Used for Contraception, Heavy menstrual bleeding (off-label/secondary indication).

At a glance

Generic nameLevonorgestrel IUS
Also known asMirena IUS, Paragard IUD, Mirena, Liletta
SponsorOregon Health and Science University
Drug classProgestin-releasing intrauterine device (IUD)
TargetProgesterone receptor
ModalitySmall molecule
Therapeutic areaContraception / Gynecology
PhaseFDA-approved

Mechanism of action

The levonorgestrel IUS delivers a continuous low dose of the progestin levonorgestrel locally within the uterine cavity over several years. This creates a hostile environment for sperm penetration by thickening cervical mucus, suppresses endometrial proliferation to prevent implantation, and partially inhibits ovulation. The local delivery minimizes systemic hormone exposure compared to oral contraceptives.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results